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Monday, Apr 5, 2021

Does data show that the Pfizer COVID-19 vaccine’s protective effects last at least six months?

April Fisher, Gigafact Foundry
yes

The Pfizer-BioNTech COVID-19 vaccine remains highly effective against the disease for at least six months after the second dose, according to the developers’ April 2021 update of clinical trial results. Pfizer said their analysis found that for at least six months, the vaccine is 91.3% effective against all COVID-19 cases, and 100% effective against severe cases as defined by the Centers for Disease Control.

Experts are still learning more about exactly how long vaccines protect against COVID-19, the CDC reports—in part because the evidence can only accumulate as time goes by. A review of vaccine progress published in Nature observes that “only time will tell how long the vaccine-elicited protection will last, and how frequent the booster injections should be administered to keep the protection fully active.”

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